A compelling new meta-analysis from a trio of accomplished psychologists suggests violent or traumatic experiences in childhood can accelerate biological signs of aging. Early puberty, rapid cellular aging, and structural brain changes could all be linked specifically to violent childhood trauma, but not chronic poverty or neglect.
For decades researchers have studied the effect of early-life adversity on a person’s physical and cognitive development. Obviously, one’s childhood experiences greatly influence mental health in later life, but more controversial has been the growing body of research pointing to possible physiological effects from negative experiences in one’s youth.
A striking 2009 study found evidence to suggest childhood trauma can actually alter a person’s genetic activity by punctuating their DNA with specific epigenetic markers. Those early studies examined how these epigenetic markers can influence the brain’s stress responses, and in some cases increase suicide risk in adulthood.
In 2018 further study detailed distinct epigenetic markers in adult victims of child abuse, suggesting not only could these molecular scars possibly serve as objective biomarkers of trauma, but questions were raised over whether these genetic markers could be passed on to subsequent generations.
This new research offers one of the largest meta-analyses of the evidence to date, spanning more than 80 detailed studies. Three biological aging markers were investigated: cellular aging, structural brain development, and onset of puberty.
“The question we were really interested in is whether all negative experiences early in life are the same in terms of how they might impact the aging process, and one of the most interesting findings of the paper is that the answer is a very clear ‘no,’” says senior author Katie McLaughlin, from Harvard University.
Negative early life experiences were divided into two groups: those involving abuse or violence, and experiences associated with neglect, deprivation or poverty. Across all three biological markers studied, signs of accelerated or abnormal aging were only detected in those subjects experiencing violence or abuse.
The study noted accelerated thinning in the ventromedial prefrontal cortex, particularly in subjects suffering trauma and violence. This brain region is known to regulate social and emotional information.
“If you’re growing up in an environment where there are constant threats around you, the network of brain regions that are involved in social and emotional processing becomes more efficient at processing threat-related information, which could accelerate processes like synaptic pruning where that network is getting rid of connections that it doesn’t need and becomes efficient more quickly for kids who are growing up in dangerous contexts,” explains McLaughlin.
Cellular epigenetic aging markers were also increased in children experiencing violence, but not those experiencing deprivation or poverty. Early onset of puberty was also specifically seen in children experiencing violent trauma.
The researchers hypothesize the possible evolutionary function of these accelerations to biological aging could be physiological adaptations to threat-filled environments. For example, reaching puberty sooner enables more rapid reproduction abilities, while the structural brain changes could help younger children better respond to dangerous environments.
Of course, these accelerations to biological aging result in profoundly negative physical and mental health consequences as children reach adulthood. Alongside the obvious psychiatric repercussions, these accelerated physiological mechanisms can heighten one's risk for cardiovascular disease, diabetes and cancer.
The research has a number of compelling implications for clinicians managing children who have suffered violence or trauma. Further research is necessary to explore whether interventions can help children offset these accelerated biological processes and prevent health consequences in adulthood.
Natalie Colich, first author on the new study from the University of Washington, also suggests these early biological markers of trauma could help doctors identify children suffering from abuse, and allow preventive measures to be employed early in development to promote healthier outcomes in adulthood.
“If you have a kid who comes into a pediatrician’s office and is showing precocious pubertal onset, you can first start to [ask] questions about the experiences this child had in early childhood and also know that this child is probably at risk for mental and physical health problems down the road,” says Colich. “So [biological aging] is a good marker for these two things that we should watch out for in order to promote a healthier trajectory of development.”
The new study was published in the journal Psychological Bulletin.
Source: Harvard University